Transferrin Isoelectric Focusing – CDG screening

Test description

Congenital disorders of glycosylation, (CDG), also known as carbohydrate deficient glycoprotein syndromes, are a collection of disorders in which many glycoproteins are deficient or have reduced carbohydrate side chains. Many subtypes of congenital disorders of glycosylation have been described based on the isoelectric focusing patterns of transferrin and on clinical features. Sialic acid is the terminal sugar residue of the two carbohydrate side chains of transferrin. Any block in the synthesis of these side chains will result in an undersialylated transferrin molecule. Because it is a major serum protein and is easily detectable, transferrin is utilized as a marker in screening for congenital disorders of glycosylation.